244 research outputs found
The Effect Of Embedded Super Hard Composite On The Production Of Super Hard Materials: Necessity
Super alloys or high performance alloys are alloys that
exhibit perfect mechanical strength and creep resistance
at high temperatures,better corrosion stability and
oxidation resistance.Super alloys are generally used in
many industrial applications that need to operate at elevated temperatures and pressures applied static and
dynamic stresses and aggressive environment due to their
extraordinary mechanical properties and surface stability.
They have the characteristic of an austenitic face-centered
cubic crystal structure with a base alloying element of
nickel,cobalt,or nickel-iron. To develop a super alloy that
will be driven by the aerospace and power industries. Chemical and process innovations are the two aspect of development of decent super alloy.It is also
a known fact that super alloys are developed through solid solution strengthening.In this contribution,sufficient knowledge of a close review of the impact of super alloy on corrosion,microstructure and mechanical characterization developed by composite embedded modifier agent will be examined.Their characteristics will be reviewed and tailored toward material application
Comparative Assessment Of The Microhardness And Plastic Degradation Mechanism Of deposited Modulated Coatings On Mild Steel
Zinc based coatings modified with aluminium and tin inclusions were electro deposited in chloride zinc sulfate electrolytes containing a metallic powder of titanium.It was found that presence of these particulates is suitable to obtain Zn AI Sn-Ti composites coating that could help in crease the micro hardnesss characteristics and wear properties. The hardness and wear properties of the deposited coatings were examined with diamond base micro-hardness tester and CETR reciprocating sliding tester respectively. The structural properties were examined with the help of scanning electron microscope.lt was observed that structural coating surface impact on the hardness propagation with increases
from 33.4 to 299 kgf mm-~(HVN4o),and shows a considerably higher wear resistance from 2.351 g/min to 0.002g/min. lt is obvious that plastic deformation of the working steel structure is dependent on protective coating and the concentration of the individual particulate
Functional interactions of the AF-2 activation domain core region of the human androgen receptor with the amino-terminal domain and with the transcriptional coactivator TIF2 (transcriptional intermediary factor2)
Previous studies in yeast and mammalian cells showed a functional
interaction between the amino-terminal domain and the carboxy-terminal,
ligand-binding domain (LBD) of the human androgen receptor (AR). In the
present study, the AR subdomains involved in this in vivo interaction were
determined in more detail. Cotransfection experiments in Chinese hamster
ovary (CHO) cells and two-hybrid experiments in yeast revealed that two
regions in the NH2-terminal domain are involved in the functional
interaction with the LBD: an interacting domain at the very NH2 terminus,
located between amino acid residues 3 and 36, and a second domain,
essential for transactivation, located between residues 370 and 494.
Substitution of glutamic acid by glutamine at position 888 (E888Q) in the
AF-2 activation domain (AD) core region in the LBD, markedly decreased the
interaction with the NH2-terminal domain. This mutation neither influenced
hormone binding nor LBD homodimerization, suggesting a role of the AF-2 AD
core region in the functional interaction between the NH2-terminal domain
and the LBD. The AF-2 AD core region was also involved in the interaction
with the coactivator TIF2 (transcriptional intermediary factor 2), as the
E888Q mutation decreased the stimulatory effect of TIF2 on AR AF-2
activity. Cotransfection of TIF2 and the AR NH2-terminal domain expression
vectors did not result in synergy between both factors in the induction of
AR AF-2 activity. TIF2 highly induced AR AF-2 activity on a complex
promoter [mouse mammary tumor virus (MMTV)], but it was hardly active on a
minimal promoter (GRE-TATA). In contrast, the AR NH2-terminal domain
induced AR AF-2 activity on both promoter constructs. These data indicate
that both the AR NH2-terminal domain and the coactivator TIF2 functionally
interact, either directly or indirectly, with the AF-2 AD core region in
the AR-LBD, but the level of transcriptional response induced by TIF2
depends on the promoter context
Including Information on Overdiagnosis in Shared Decision Making : A Review of Prostate Cancer Screening Decision Aids
Publisher Copyright: © The Author(s) 2022.Background. Overdiagnosis is an accepted harm of cancer screening, but studies of prostate cancer screening decision aids have not examined provision of information important in communicating the risk of overdiagnosis, including overdiagnosis frequency, competing mortality risk, and the high prevalence of indolent cancers in the population. Methods. We undertook a comprehensive review of all publicly available decision aids for prostate cancer screening, published in (or translated to) the English language, without date restrictions. We included all decision aids from a recent systematic review and screened excluded studies to identify further relevant decision aids. We used a Google search to identify further decision aids not published in peer reviewed medical literature. Two reviewers independently screened the decision aids and extracted information on communication of overdiagnosis. Disagreements were resolved through discussion or by consulting a third author. Results. Forty-one decision aids were included out of the 80 records identified through the search. Most decision aids (n = 32, 79%) did not use the term overdiagnosis but included a description of it (n = 38, 92%). Few (n = 7, 17%) reported the frequency of overdiagnosis. Little more than half presented the benefits of prostate cancer screening before the harms (n = 22, 54%) and only 16, (39%) presented information on competing risks of mortality. Only 2 (n = 2, 5%) reported the prevalence of undiagnosed prostate cancer in the general population. Conclusion. Most patient decision aids for prostate cancer screening lacked important information on overdiagnosis. Specific guidance is needed on how to communicate the risks of overdiagnosis in decision aids, including appropriate content, terminology and graphical display. Most patient decision aids for prostate cancer screening lacks important information on overdiagnosis. Specific guidance is needed on how to communicate the risks of overdiagnosis.Peer reviewe
Neurolin Ig Domain 2 Participates in Retinal Axon Guidance and Ig Domains 1 and 3 in Fasciculation
The optic disk–directed growth of retinal ganglion cell axons is markedly disturbed in the presence of polyclonal antineurolin antibodies, which mildly affect fasciculation (Ott, H., M. Bastmeyer, and C.A.O. Stuermer, 1998. J. Neurosci. 18:3363–3372)
Amino acids 3-13 and amino acids in and flanking the 23FxxLF27 motif modulate the interaction between the N-terminal and ligand-binding domain of the androgen receptor
The N-terminal domain (NTD) and the ligand-binding domain (LBD) of the
androgen receptor (AR) exhibit a ligand-dependent interaction (N/C
interaction). Amino acids 3-36 in the NTD (AR3-36) play a dominant role in
this interaction. Previously, it has been shown that a PhixxPhiPhi motif
in AR3-36, 23FxxLF27, is essential for LBD interaction. We demonstrate in
the current study that AR3-36 can be subdivided into two functionally
distinct fragments: AR3-13 and AR16-36. AR3-13 does not directly interact
with the AR LBD, but rather contributes to the transactivation function of
the AR.NTD-AR.LBD complex. AR16-36, encompassing the 23FxxLF27 motif, is
predicted to fold into a long amphipathic alpha-helix. A second
PhixxPhiPhi candidate protein interaction motif within the helical
structure, 30VREVI34, shows no affinity to the LBD. Within AR16-36, amino
acid residues in and flanking the 23FxxLF27 motif are demonstrated to
modulate N/C interaction. Substitution of Q24 and N25 by alanine residues
enhances N/C interaction. Substitution of amino acids flanking the
23FxxLF27 motif by alanines are inhibitory to LBD interaction
Extracts of six Rubiaceae species combined with rifampicin have good in vitro synergistic antimycobacterial activity and good anti-inflammatory and antioxidant activities
BACKGROUND : The Rubiaceae family has played a significant role in drug discovery by providing molecules with
potential use as templates for the development of therapeutic drugs. This study was designed to study the in
vitro synergistic effect of six Rubiaceae species in combination with a known anti-TB drug. The antioxidant and
anti-inflammatory activity of these species were also evaluated to investigate additional benefits in antimycobacterial
treatment.
METHODS : The checkerboard method was used to determine the antimycobacterial synergistic activity of plant
extracts combined with rifampicin. The antioxidant activity of extracts was determined by the 2,2-diphenyl-
1-picrylhydrazyl (DPPH) method. Anti-inflammatory activity via inhibition of nitric oxide (NO) production was
performed in LPS-activated RAW 264.7 macrophages using the Griess assay.
RESULTS : Combination of rifampicin with the crude extracts resulted in a 4 to 256-fold increase of activity
of extracts. The crude extract of Cremaspora triflora produced the best synergistic effect with rifampicin, with
a fractional inhibitory concentration (FIC) index of 0.08 against Mycobacterium aurum. Extracts of Psychotria
zombamontana had the best antioxidant activity with an IC50 value of 1.77 ÎĽg/mL, lower than the IC50 of
trolox and ascorbic acid (5.67 ÎĽg/mL and 4.66 ÎĽg/mL respectively). All the extracts tested inhibited nitric oxide (NO)
production in a concentration dependent manner with the percentage of inhibition varying from 6.73 to 86.27 %.
CONCLUSION : Some of the Rubiaceae species investigated have substantial in vitro synergistic effects with rifampicin
and also good free radical scavenging ability and anti-inflammatory activity. These preliminary results warrant further
study on these plants to determine if compounds isolated from these species could lead to the development
of bioactive compounds that can potentiate the activity of rifampicin even against resistant mycobacteria.The University of Pretoria Institutional Research Theme for Animal and
Zoonotic Diseases (IRT-AZD), National Research Foundation (NRF,
Grant No 81010) and Medical Research Council (MRC) of South
Africa provided funding to support this study. The National Research
Foundation
(NRF) provided a doctoral fellowship to AOA. The University of Pretoria
provided a postdoctoral fellowship to JPD.http://www.biomedcentral.com/bmccom/plementalternmedam2017Paraclinical Science
Field-Induced Magnetization Steps in Intermetallic Compounds and Manganese Oxides: The Martensitic Scenario
Field-induced magnetization jumps with similar characteristics are observed
at low temperature for the intermetallic germanide Gd5Ge4and the mixed-valent
manganite Pr0.6Ca0.4Mn0.96Ga0.04O3. We report that the field location -and even
the existence- of these jumps depends critically on the magnetic field sweep
rate used to record the data. It is proposed that, for both compounds, the
martensitic character of their antiferromagnetic-to-ferromagnetic transitions
is at the origin of the magnetization steps.Comment: 4 pages,4 figure
The T=0 neutron-proton pairing correlations in the superdeformed rotational bands around 60Zn
The superdeformed bands in 58Cu, 59Cu, 60Zn, and 61Zn are analyzed within the
frameworks of the Skyrme-Hartree-Fock as well as Strutinsky-Woods-Saxon total
routhian surface methods with and without the T=1 pairing correlations. It is
shown that a consistent description within these standard approaches cannot be
achieved. A T=0 neutron-proton pairing configuration mixing of
signature-separated bands in 60Zn is suggested as a possible solution to the
problem.Comment: 9 ReVTex pages, 10 figures, submitted to Phys. Rev.
Forensic psychiatry in Africa : prospects and challenges
Forensic Psychiatry has a history that dates back almost two thousand years, and has evolved into a recognised discipline with a robust background of scientific enquiry, mostly because mental health care has always had an important interface with the law. Nevertheless, even in the developed world there are differences between countries with respect to the extent forensic mental health services have developed. This has been exacerbated by the differences in legal systems, resources and priorities in each country. Consequently comparisons and cooperation between forensic psychiatrists internationally has been difficult. In Africa, which is the second largest and most populous continent and containing an immense diversity of languages, religious traditions, ethnic groups and sociopolitical systems forensic psychiatry has largely remained underdeveloped within the context of a pervasive neglect in the provision of mental health services. The situation is compounded by the dearth of information about forensic services on the continent. As described by an eminent African psychiatrist, "the practice of forensic psychiatry in Africa is shrouded in both mystery and confusion". In addition to the lack of appropriate facilities, most countries in Africa have, on average, one psychiatrist per one million inhabitants. Moreover many psychiatrists have migrated to developed countries, leaving a small number of mental health professionals burdened with large numbers of patients.http://www.journals.co.za/ej/ejour_medjda.htm
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